I have a Marshall JVM410HJS (serial fx loop) that I am trying to integrate my hd500x with via 4cm. I seem to have everything connected properly. All effects before the preamp (in front of the fx loop block) work fine but when trying to putting any after the fx loop block (ie reverbs, delay, etc.) I am getting no sound from those effects. Moving them in front of the fx loop block is allowing them to work but I want them after the pre-amp of my Marshall not before. Any idea what I'm not understanding or missing would be greatly appreciated. Thanks!